Intermodal fiber interferometer with frequency scanning laser for sensor application.

Area of Science:

• Optoelectronics
• Fiber Optics
• Signal Processing

Background:

• Interferometric fiber sensors are susceptible to signal fading and nonlinear responses.
• Existing methods for signal stabilization and linearization are often complex or limited.

Purpose of the Study:

• To develop an intermodal fiber interferometer with a frequency scanning light source.
• To eliminate signal fading and achieve a linear response to external fiber perturbations.
• To demonstrate a novel signal processing technique for improved sensor performance.

Main Methods:

• Utilizing an optical frequency scanning light source in an intermodal fiber interferometer.
• Employing autocorrelation function analysis of repeated interferometric signal traces for signal averaging.
• Proposing and theoretically analyzing modifications to the correlation function for signal reconstruction.

Main Results:

• Demonstrated complete signal reconstruction through correlation-based signal processing.
• Established a direct relationship between the autocorrelation function and the averaged amplitude characteristic.
• Experimentally confirmed the efficiency of the proposed interferometer and signal processing for sine-shaped fiber length modulation.

Conclusions:

• The proposed intermodal fiber interferometer effectively eliminates signal fading and achieves linear response.
• The correlative signal processing method enables robust signal reconstruction and averaging.
• This approach holds significant potential for real-time fiber optic sensing applications.